Shaft locking device



March 2, 1965 J. E. KELLY ETAL SHAFT LOCKING DEVICE Filed March 12, 1962 llll Jo/.w E. Kell /Pec ery,

United States Patent O 3,171,521 SHAFT LGCKING DEVICE John E. Kelly, Burbank, and Sig R. Rechberg, Tujunga,

Calif., assignors to Adams Rite Manufacturing Company, Glendale. Calif., a corporation of California Filed Mar. 12, 1962, Ser. No. 178,807 7 Claims. (Cl. 192-8) The present invent-ion relates generally to a device for rotatively driving a shaft-like element in one direction and releasably locking the same against reverse drive rotation.

It is one object of the herein described invention to provide an improved device for lthe purpose set forth which is of simple, compact, and rugged construction, and in which the -driving element may be varied or modified readily to adapt the device to different installation requirements.

A further object of the invention is to provide an improved shaft locking device wherein the driving and driven elements are operatively associated and rotatably mounted in a housing structure which forms a single support for the device.

Another object is to provide such a device in which the locking elements are mounted on and carried by a single shaft, the locking elements being substantially sealed and protected from dust and other surrounding media which might seriously affect the device operation.

Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is Afor the purpose of fully `disclosing the invention Without placing limitations thereon.

Referring to the accompanying drawings, which are for illustrative purposes only:

FIG. 1 is an elevational view of a shaft locking device embodying the features of the present invention;

FIG. 2 is an end view of the same looking towards the driven shaft end;

FIG. 3 is an enlarged axial section taken substantially on a line 3-*3 of FIG. 2, certain parts being shown in elevation to clarify the arrangement;

FIG. 4 is an enlarged transverse sectional view taken substantially on line 4-*4 of FIG. l; and

e FIG. 5 is a fragmentary sectional View taken substantially on line 5-5 of FIG. 4 to show certain details of construction of the locking bar and its mounting.

Referring more specifically to the drawings, the shaft locking device of the present invention is shown as comprising generally a cylindrical housing llti having a cupped body portion 11 and a radially extending peripheral flange 12 at the cup brim, this ange having a plurality of circumferentially spaced openings 13 which permit fixedly mounting of the housing in an operative position.

A release member, as generally indicated by the numeral 14, is rotatably mounted in the housing 10, the release member constituting a drive element of the device. As will best be seen from FIG. 3, the release member comprises a generally cylindrical structure which includes an outer end annular flange 15 which is adapted to overlie the inner margin of the radial flange 12 and form limiting engagement therewith which serves to position an inner cylindrical end 16 thereof within the body portion 11 of the housing. The end 16 has its outermost surface 17 in bearing engagement with the adjacent inner wall surface 18 which constitutes a cylindrical braking surface. Interiorly the release member is constructed with an inner annular radially projecting flange `19 which is positioned between the ends of the release member and is provided with an axial opening 20.

As a driving member, various arrangements may be utlized to connect the release member with the driving mechanism. In the illustrated embodiment, the annular ice flange 15 is shown as being simply provided with diametrically positioned threaded openings 21-21 which permit attachment to an operating lever or other means by which the release member may be rotated. As shown in FIG. 4, the end -16 of the release member is arranged so as to in effect -forrn a pair of axially projecting arcuate fianges 16a and 16h which have their adjacent ends in spaced apart relation to provide diametrically arranged openings 22 and 23 which expose portions therein of the inner wall braking surface 18. The opening 22 is defined by the flange ends l22a and 22b, while the opening 23 is formed by the flange ends 23a and 23b.

Referring again to FIG. 3, a shaft 24, which forms a driven element in this case, is rotatably mounted in the opening 20 and an axial opening 25 of the body portion 11, these openings having wall surfaces which provide axially spaced bear-ings for the shaft. One end of the shaft 24 projects outwardly of the flange 19 and is fitted with a retaining snap ring 26. The other end of the shaft 24 projects outwardly of the body portion 11 and is fitted with a retaining snap ring 27. This end of the shaft may be splined, if desired, as shown at 28. The snap rings 26 and 27 thus retain the shaft 24, housing 10 and release member 14 in assembled operative relationship. As thus assembled, it will be apparent that the housing 10 forms a support in which the release member 14 is rotatably mounted, and that the housing and release member cooperatively provide bearing supports `for the shaft 24.

As thus far described, the release member drive element and the shaft 24 driven element are supported for independent rotative movements.

The shaft locking mechanism will now be described. At a position between the spaced bearings of the shaft 24, the shaft is provided with a transverse passage 29 to rectangular cross section in which a locking bar 30 is loosely mounted for lateral and tilting movements, the ends of the bar respectively extending outwardly beyond the shaft 24 periphery into the openings 22 and 23 for engagement with the exposed braking surface therein. As shown best in FIGS. 4 and 5, the locking bar is fabricated from rectangular section stock material and has its corner edges slightly bevelled. At the ends of the bar, relatively long bevelled end surfaces 31-31 are provided so that braking surfaces 32-32 will be formed in offset relation with respect to the longitudinal symmetrical axis of the bar 30. The surfaces 32-32 are formed with a proper curvature to brakingly engage the inner wall braking surface 13 of the housing 10. The top edge of the bar 30, as seen in FIG. 4 is provided with a longitudinally extending groove 33 which is adapted to receive therein a spring member 34.

The spring member 34 is formed Ifrom a strip of spring material which is deflected intermediate its ends to form a portion 35 which is adapted to extend into the groove 33 and steady the -spr-ing in its mounted position. The ends of the spring respectively extend outwardly beyond the outer surface of the shaft 24 and are provided with reduced end finger portions 36--36 which curve downwardly into engagement with the surfaces 31-31 respectively. As thus arranged, the spring 34 normally biases the bar 36 in a lateral direction so that it rides close to fiange end edges 22b and 23b, in which position the bar end braking surfaces 32-32 are wedgingly engaged with the braking surface 18. This is the normal position of the bar.

Having the bar 30 in its normal position, it will be apparent that, if the release member 14 is rotated in either direction by the application of a rotating force, the end edge 22b or 23b, depending upon the direction of rotation, will act to tilt the locking bar 30 to a released position with respect to the braking surface. Since the locking carry the shaft 24 with it and unitary rotation will result. l However, if it is attempted to reverse drive the shaft 24 by applying a rotative force thereto, such movementk will cause the shaft edge 37a or 37b at the ends of the passage 29, depending upon the directionof rotation, to

move the locking bar 30 more forcefully in a lockingV direction so thatl the shaft 24 willA be lockedv and retained against rotation.

Various modifications may suggest themselves'tothose skilled in the art without departing from the spirit of our invention, and, hence, we do not wishto be restricted to the specic form shown or uses mentioned, except to the extent indicated in the appended claims.-

We claim:

1. A shaft locking device, comprising:

(A) a brake member having a circular braking surface;

(B) a rotatably mounted shaft having an axis of rotation common to the axisof said braking surface;

(C) a locking bar carried by said shaft and supportedv v v thereon for limited lateral and tilting movement,

ends lying on one side of a longitudinal axis of f said locking bar; (D) a springv carried-by said Vshaft acting between an adjacent part of said shaft and said locking bar for normally biasing said locking bar laterally towards a locking position with its end surfaces in engagey.

ment with said braking surface,.whereby the shaft isfV held against movement relative to said braking surface when a rotative force` is applied to said shaft; and i Y v (E) a rotatable release member having an vaxis of rotation common to the axis of said shaft adapted to engage andV releasesaid locking `bar in response to movement in either ,of Vits directions ofV rotation,

whereby to permit unitary rotation'of the ,releasey member and said shaft` when a rotative force is-applied to the release member.

2. A shaft locking device, comprising:

(A) VA housing having a'circular braking surface;

(B) a release member supported on said housing for' j rotation; Y Y. (C) a shaft'extending axially of said release member and said housing, t

(a) said shaft having bearing supports in said housing and said release member; (D) a locking bar loosely mounted-on said shaft between said bearing supports for rotation therewith,} but having slight` independent Ymovementsy relative f thereto, Y Y Y (a) said bar havingend surfaces normally engaging said braking surface and beingnadapted to loclf;l said housing and-shaft against relative movements when a rotative force is applied in either direction tosaid shaft; andY K Y Y (E) means carried' by said release member for engag-` ing Vand moving said locking bar to areleased-posi- Y tion inresponse torespective rotative movements of saidrelease member in oppositev directions, whereby to permit unitary rotation of therelease member and said shaftwhen a rotativeforce is applied in'either direction to the release-member.V

3`. A shaft locking device, comprising: y Y

(A) a housing having a circularA braking surface; Y

(B) a release member supported on said housing for rotation;

(C) a shaft extending axiallyof said'release member and said housing,

(a) said shaft having bearing supports in said housingand said release member, and

(b) saidY shaft'Y having a transverse opening posi.

tioned- Vbetween saidV bearingsupp'orts; Y (D) a locking bar extending loosely throughV said shaft opening, Y

(a) vsaid bar having end surfaces engageable withy said braking surface;

(E) yieldable means between said shaft and bar normally urging the bar in a direction to press said end Vsurfaces against thev braking surface and lock said housing and shaft against relative movement when a rotative force is applied in 'either direction to saidshaft; :and

(F) means carried by4 said release member for engaging and moving said locking bar to-a released position in response to respective rotative movements of said release member in opposite directions, whereby to Vpermit; unitaryrotation of the release member and said shaft when'a rotative force isapplied tothe release member. t

4. A shaft locking device, comprising:

, (A) a housing having. aV circularV brakingV surface;

(B) a release member having ra curved flangein bearing relation with said braking surface and supporting: said release member for rotation about an axis coin-- Y cident with said braking surface axis,

(a) said Aflange-'having diametrical openings there-- in;` (C) al shaft having rotation bearing supports in said housing and said release member; (D) a locking bar carried by said shaft and supported l thereon between said shaft bearing supports for limit- `ed lrelative tilting movement,

(a) said bar having its opposite ends extending throughy saidange openings and provided with Y 'Curved surfaces; and (E) a spring normally biasing said locking bar towards a locking position with its end surfaces in' engagement with said braking surface, whereby Vthe shaft is held against movementrelative to said brakingA surface when a rotative-force is appliedl to said shaft,

(a) said locking bar being movable/to non-lock- Y ing position rby said flange at said openings when a rotative'force is applied to Ysaid release member. Y j Y e 5.' A shaft locking device, comprising:V

(A) a housing having-a circular braking surface;

(B) a release member having'a curved angein bearing relation with saidY braking surface and supporting release'memberfor rotation about an axis coincident (a) said barfrhavingitsopposite-'ends extendingV Y t through said flangeopenings and provided with Y VcurVed surfaces;rand i (E) aspring'carried by said-.shaftrnormally'biasing said locking bar towards, a locking position with its end surfaces in Vengagement with vsaid brakingrsurface, whereby the shaft is held against movement 'reflative to said braking vsurface when a rotative force Vis applied to'said shaft, f t v (a) said; locking bar being movablegto non-locking k position by said' flange at said openings when V bef; v

face; Y Y.

Y (B)V a release memberfhaving curved'tiange portions in Y bearinglrelation with said braking surface` and supporting Vsaid'releasemember'for' rotationl about an v a rotative forceis applied to said` release memaxis coincident with the axis of said braking surface,

(a) said flange portions forming diametrically positioned openings exposing braking surface portions;

(C) a rotatable shaft having,

(a) bearing supports in said housing and said release member, and

(b) a transverse opening therethrough positioned between said bearing supports;

(D) a locking bar loosely supported in said opening for limited lateral and limited tilting movements, said bar having its opposite ends extending through said openings for engaging the exposed braking surface portions therein; and

(E) a bowed leaf spring positioned in said shaft opening between a wall of said shaft opening and said locking bar biasing the bar laterally into a shaft locking position with its ends in engagement with said braking surface portions,

(a) said locking bar being tiltably movable to nonlocking position in response to rotation of said release member so as to engage a flange edge portion at one of said diametrical openings with the adjacent end of said locking bar.

7. A shaft locking device, comprising:

(A) a housing member having a circular braking surface;

(B) a release member having curved flange portions in bearing relation with said braking surface and supporting said release member for rotation about an axis coincident with the axis of said braking surface,

(a) said flange port-ions forming diametrically positioned openings exposing braking surface portions;

6 (C) a rotatable shaft having,

(a) bearing supports in said housing and said release member, and

(b) a transverse diametral opening therethrough positioned between said bearing supports;

(D) an alongate straight sided locking bar loosely supported in said opening for limited lateral and limited tilting movements, said bar having its opposite ends extending through said openings for engaging the exposed braking surface portions therein; and

(E) a leaf spring extending through said shaft opening having an intermediate bowed portion between a wall of said shaft openings and said locking bar biasing the bar laterally into a shaft locking position with its ends in engagement with said braking surface portions, and projecting end curved portions respectively engaging the ends of said locking bar outwardly of said shaft,

(a) said locking bar being tiltable movable to nonlocking position by said flange portions at said openings when a rotative force Ais applied in either direction to said release member.

References Cited in the ile of this patent UNITED STATES PATENTS 2,347,293 Smith Apr. 23, 1944 2,359,010 Smith Sept. 26, 1944 2,573,939 Verville et al Nov. 6, 1951 2,873,832 Helm Feb. 17, 1959 2,995,225 Cline Aug. 8, 1961 3,051,282 Greene Aug. 28, 1962 FOREIGN PATENTS 588,091 Great Britain May 14, 1947 

1. A SHAFT LOCKING DEVICE, COMPRISING: (A) A BRAKE MEMBER HAVING A CIRCULAR BRAKING SURFACE; (B) A ROTATABLY MOUNTED SHAFT HAVING AN AXIS OF ROTATION COMMON TO THE AXIS OF SAID BRAKING SURFACE; (C) A LOCKING BAR CARRIED BY SAID SHAFT AND SUPPORTED THEREON FOR LIMITED LATERAL AND TILTING MOVEMENT, ENDS LYING ON ONE SIDE OF A LONGITUDINAL AXIS OF SAID LOCKING BAR; 